Linguistically, Indo-Aryan languages display Afro-Dravidian influence: "Accordingly, the introduction of cacuminal sounds into the Aryan languages of India when that country was invaded by unpolished Nordic peoples is due to the influence of Dravidian Negroes." - 'Nations nègres et culture' Cheikh Anta Diop, NY: Lawrence Hill, 1974, p 116.

1) "The ethnic history of India would seem to be first a prehistoric substratum of Negrillos or black dwarfs, then the pre-Dravidians, a taller, larger type of Negro; then the Dravidians, Negroes with some mixture of Mongoloid & later of Caucasoid stocks. The Dravidian Negroes laid the basis of Indian culture thousands of years before the Christian era. On these descended through Afghanistan an Asiatic or Eastern European element, usually called Aryan.
The Rig Veda, ancient sacred hymns of India, tells of the fierce struggles between these whites & blacks for the mastery of India. It sings of Aryan deities who rushed furiously into battle against the black foe. The hymns praise Indra, the white deity, for having killed fifty thousand blacks, 'piercing the citadel of the enemy' & forcing the blacks to run out in distress, leaving all their food & belongings." - 'W.E.B. Du Bois on Asia: Crossing the World Color Line' W E B Du Bois. eds. B Mullen & C Watson. Jackson: Uni Press of Miss., 2005, p 9.

2) "... India, before being invaded by white people, was altogether peopled by Negroes, for the very simple reason that its present pop.n is made up of Dravidian Negroes." - 'Weights for Weighing Gold' Georges Niangoran-Bouah. Présence Africaine v 17-20 (1963) 193-210: p 206.